Genesis-Plus-GX/source/ngc/ngc.c

274 lines
6.1 KiB
C

/****************************************************************************
* ngc.c
*
* Genesis Plus GX main
*
* code by Softdev (2006), Eke-Eke (2007,2008)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
***************************************************************************/
#include "shared.h"
#include "font.h"
#include "history.h"
#include "gcaram.h"
#ifdef HW_DOL
#include "dvd.h"
#else
#include <di/di.h>
#endif
#include <fat.h>
int Shutdown = 0;
#ifdef HW_RVL
/* Power Button callback */
void Power_Off(void)
{
Shutdown = 1;
ConfigRequested = 1;
}
#endif
/***************************************************************************
* Genesis Plus Virtual Machine
*
***************************************************************************/
static void load_bios()
{
char pathname[MAXPATHLEN];
/* reset BIOS found flag */
config.bios_enabled &= ~2;
/* open BIOS file */
sprintf (pathname, "%s/BIOS.bin",DEFAULT_PATH);
FILE *fp = fopen(pathname, "rb");
if (fp == NULL) return;
/* read file */
fread(bios_rom, 1, 0x800, fp);
fclose(fp);
/* update BIOS flags */
config.bios_enabled |= 2;
if (config.bios_enabled == 3)
{
/* initialize system */
system_init ();
audio_init(48000);
}
}
static void init_machine (void)
{
/* Allocate cart_rom here */
cart_rom = memalign(32, 10 * 1024 * 1024);
/* BIOS support */
load_bios();
/* allocate global work bitmap */
memset (&bitmap, 0, sizeof (bitmap));
bitmap.width = 720;
bitmap.height = 576;
bitmap.depth = 16;
bitmap.granularity = 2;
bitmap.pitch = bitmap.width * bitmap.granularity;
bitmap.viewport.w = 256;
bitmap.viewport.h = 224;
bitmap.viewport.x = 0;
bitmap.viewport.y = 0;
bitmap.data = texturemem;
/* default system */
input.system[0] = SYSTEM_GAMEPAD;
input.system[1] = SYSTEM_GAMEPAD;
}
/**************************************************
Load a new rom and performs some initialization
***************************************************/
void reloadrom ()
{
load_rom(""); /* Load ROM */
system_init (); /* Initialize System */
audio_init(48000); /* Audio System initialization */
ClearGGCodes (); /* Clear Game Genie patches */
system_reset (); /* System Power ON */
}
/***************************************************************************
* M A I N
*
***************************************************************************/
int FramesPerSecond = 0;
int frameticker = 0;
bool fat_enabled = 0;
int main (int argc, char *argv[])
{
#ifdef HW_RVL
/* initialize Wii DVD interface first */
DI_Close();
DI_Init();
#endif
u16 usBetweenFrames;
long long now, prev;
int RenderedFrameCount = 0;
int FrameCount = 0;
/* Initialize OGC subsystems */
ogc_video__init();
ogc_input__init();
ogc_audio__init();
#ifdef HW_DOL
/* Initialize GC DVD interface */
DVD_Init ();
dvd_drive_detect();
#endif
#ifdef HW_RVL
/* Power Button callback */
SYS_SetPowerCallback(Power_Off);
#endif
/* Initialize FAT Interface */
if (fatInitDefault() == true)
{
fat_enabled = 1;
#ifdef HW_RVL
fatEnableReadAhead ("sd", 6, 64);
fatEnableReadAhead ("usb", 6, 64);
#else
fatEnableReadAhead ("carda", 6, 64);
fatEnableReadAhead ("cardb", 6, 64);
#endif
}
/* Default Config */
legal();
set_config_defaults();
config_load();
/* Restore Recent Files list */
set_history_defaults();
history_load();
/* Initialize Virtual Machine */
init_machine ();
/* Load any injected rom */
if (genromsize)
{
ARAMFetch((char *)cart_rom, (void *)0x8000, genromsize);
reloadrom ();
}
/* Show Menu */
MainMenu();
ConfigRequested = 0;
/* Initialize Frame timings */
frameticker = 0;
prev = gettime();
/* Emulation Loop */
while (1)
{
/* Frame synchronization */
if (gc_pal != vdp_pal)
{
/* use timers */
usBetweenFrames = vdp_pal ? 20000 : 16666;
now = gettime();
if (diff_usec(prev, now) > usBetweenFrames)
{
/* Frame skipping */
prev = now;
system_frame(1);
}
else
{
/* Delay */
while (diff_usec(prev, now) < usBetweenFrames) now = gettime();
/* Render Frame */
prev = now;
system_frame(0);
RenderedFrameCount++;
}
}
else
{
/* use VSync */
if (frameticker > 1)
{
/* Frame skipping */
frameticker--;
system_frame (1);
}
else
{
/* Delay */
while (!frameticker) usleep(10);
system_frame (0);
RenderedFrameCount++;
}
frameticker--;
}
/* update video & audio */
ogc_video__update();
ogc_audio__update();
/* Check rendered frames (FPS) */
FrameCount++;
if (FrameCount == vdp_rate)
{
FramesPerSecond = RenderedFrameCount;
RenderedFrameCount = 0;
FrameCount = 0;
}
/* Check for Menu request */
if (ConfigRequested)
{
/* reset AUDIO */
ogc_audio__reset();
/* go to menu */
MainMenu ();
ConfigRequested = 0;
/* reset frame timings */
frameticker = 0;
prev = gettime();
FrameCount = 0;
RenderedFrameCount = 0;
}
}
return 0;
}